def stack_test(source):
"""
-------------------------------------------------------
Tests the methods of Stack for empty and
non-empty stacks using the data in source:
is_empty, push, pop, peek
(Testing pop and peek while empty throws exceptions)
Use: stack_test(source)
-------------------------------------------------------
Parameters:
source - list of data (list of ?)
Returns:
None
-------------------------------------------------------
"""
stack = Stack()
print('Test is empty?')
print(stack.is_empty())
print(array_to_stack(stack, source))
print('Test is empty?')
print(stack.is_empty())
print('Test for peek value: ')
print(stack.peek())
print('Test for push value: ')
stack.push(1)
print('Test for peek value: ')
print(stack.peek())
print('Test for pop value: ')
stack.pop()
print('Test is empty?')
print(stack.is_empty())
print('Test for peek value: ')
print(stack.peek())
def stack_test(source):
"""
-------------------------------------------------------
Tests the methods of Stack for empty and
non-empty stacks using the data in source:
is_empty, push, pop, peek
(Testing pop and peek while empty throws exceptions)
Use: stack_test(source)
-------------------------------------------------------
Parameters:
source - list of data (list of ?)
Returns:
None
-------------------------------------------------------
"""
s = Stack()
print("Stack Initialised")
print()
print(SEP)
print("Stack is_empty (expect True): {}".format(s.is_empty()))
print(SEP)
print("Add one item to Stack:")
s.push(source[0])
print("Top of Stack (peek):")
print(s.peek())
print(SEP)
print("Stack is_empty (expect False): {}".format(s.is_empty()))
print(SEP)
print("Stack pop:")
v = s.pop()
print(v)
print(SEP)
print("Stack is_empty (expect True): {}".format(s.is_empty()))
print(SEP)
print("Copy all data to Stack")
array_to_stack(s, source)
print(SEP)
print("Stack is_empty (expect False): {}".format(s.is_empty()))
print(SEP)
print("Top of Stack (peek):")
print(s.peek())
print(SEP)
print("Remove all elements from Stack")
while not s.is_empty():
v = s.pop()
print(v)
print()
print(SEP)
print("Stack is_empty (expect True): {}".format(s.is_empty()))
print()
return
def has_balanced_brackets(string):
"""
-------------------------------------------------------
Determines if a string contains balanced brackets or not. Non-bracket
characters are ignored. Uses a stack. Brackets include {}, [], (), <>.
Use: balanced = has_balanced_brackets(string)
-------------------------------------------------------
Parameters:
string - the string to test (str)
Returns:
balanced (int) -
BALANCED if the brackets in string are balanced
MISMATCHED if the brackets in string are mismatched
MORE_RIGHT if there are more right brackets than left in string
MORE_LEFT if there are more left brackets than right in string
-------------------------------------------------------
"""
right = 0
left = 0
s = Stack()
for x in string:
if s.is_empty() == True:
s.push(x)
elif s.peek() == '[' and x == ']' or s.peek(
) == '(' and x == ')' or s.peek() == '{' and x == '}' or s.peek(
) == '<' and x == '>':
s.pop()
else:
s.push(x)
if s.is_empty() == True:
balanced = 0
else:
while s.is_empty() == False:
x = s.pop()
if x == '(' or x == '[' or x == '{' or x == '<':
left += 1
elif x == ')' or x == ']' or x == '}' or x == '>':
right += 1
if right > left:
balanced = 2
elif left > right:
balanced = 1
else:
balanced = 3
return balanced
def stack_test(source):
"""
-------------------------------------------------------
Tests the methods of Stack for empty and
non-empty stacks using the data in source:
is_empty, push, pop, peek
(Testing pop and peek while empty throws exceptions)
Use: stack_test(source)
-------------------------------------------------------
Parameters:
source - list of data (list of ?)
Returns:
None
-------------------------------------------------------
"""
s = Stack()
# Test if stack is empty (Expected: TRUE)
print("Stack contents: ")
for i in s:
print(i, end=' ')
print("\tEmpty? {}".format(s.is_empty()))
# Load elements from source into Stack
print(">> Push elements from source onto stack")
print(">> Num elements to push: {}".format(len(source)))
for elem in source:
s.push(elem)
# Check if the Stack is empty again (T/F depending on source contents)
print("Stack contents: ")
for i in s:
print(i, end=' ')
print("\tEmpty? {}".format(s.is_empty()))
# Peek the top of the stack
top = None
try:
top = s.peek()
except:
print(">>! Peeked at an empty stack, assertion caught, continuing...")
# Check if top of stack is the end element of source
print("Top of stack should be same as end of list")
if s.is_empty():
print("List empty so no check")
else:
top_same = top == source[-1]
print("Top same as end of list?")
print("Top: {}\tEnd of list: {}".format(top, source[-1]))
print("Same? {}".format(top_same))
# Testing pop
try:
print(">> Pop top of stack")
popped = s.pop()
print("Popped value should be same as end of list.\tSame? {}".format(popped == source[-1]))
except:
print(">>! Popped from an empty stack, exception caught, continuing...")
return
def stack_test(source):
"""
-------------------------------------------------------
Tests the methods of Stack for empty and
non-empty stacks using the data in source:
is_empty, push, pop, peek
(Testing pop and peek while empty throws exceptions)
Use: stack_test(source)
-------------------------------------------------------
Parameters:
source - list of data (list of ?)
Returns:
None
-------------------------------------------------------
"""
stack = Stack()
dummy = []
if stack.is_empty() == True:
print('Stack is empty.')
array_to_stack(stack, source)
print('Converting source into a stack...')
if stack.is_empty() == False:
print('source has been transferred into stack!')
print('\nPopping stack...')
while stack.is_empty() == False:
temp = stack.pop()
print(temp)
dummy.append(temp)
print('\nstack is empty. Pushing values back into stack...')
while dummy != []:
temp = dummy.pop()
print(temp)
stack.push(temp)
print('\nPushing complete! Peeking...')
print(stack.peek())
return
def stack_test(source):
"""
-------------------------------------------------------
Tests the methods of Stack for empty and
non-empty stacks using the data in source:
is_empty, push, pop, peek
(Testing pop and peek while empty throws exceptions)
Use: stack_test(source)
-------------------------------------------------------
Parameters:
source - list of data (list of ?)
Returns:
None
-------------------------------------------------------
"""
s = Stack()
array_to_stack(s, source)
print(s.is_empty())
print(s.peek())
print(s.pop())
s.push(1)
return
from Stack_array import Stack
values = [1, 2, 3, 4]
print("Values: {}".format(values))
s = Stack()
print(">> Is the stack empty?")
empty = s.is_empty()
print("Expect: {}\tGot: {}".format(True, empty))
print(">> Pushing values onto Stack")
for val in values:
s.push(val)
print("Stack contents: ", end='')
print("Expect: {}\tGot: ".format(values[::-1]), end='')
for elem in s:
print(elem, end=' ')
print()
print(">> Pop top of stack")
value = s.pop()
print("Expect: {}\tGot: {}".format(values[-1], value))
print(">> Peek the top of the stack")
peeked = s.peek()
print("Expect: {}\tGot: {}".format(values[-2], peeked))
""" ------------------------------------------------------------------------ Lab 2, Task 2 - utilities#array_to_stack ------------------------------------------------------------------------ Author: Nicolas Mills ID: 180856100 Email: [email protected] __updated__ = 2019-01-21 ------------------------------------------------------------------------ """ from utilities import array_to_stack from Stack_array import Stack array = [0, 1, 2, 3, 4] s = Stack() print("Array: {}".format(array)) array_to_stack(s, array) print("Values: {}".format(s._values)) print("Stack to Array: ") for elem in s: print(elem, end=' ') print() print("Array: {}".format(array)) print("Top: {}".format(s.peek()))